ETSI TS V4.1.1 ( )

Transcription

1 TS V4.1.1 ( ) Technical Specification Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); Point-to-Point (PP) Short Message Service (SMS) support on mobile radio interface (3GPP TS version Release 4) GLOBAL SYSTEM FOR MOBILE COMMUNICATIONS R

2 1 TS V4.1.1 ( ) Reference RTS/TSGN v411 Keywords GSM, UMTS 650 Route des Lucioles F Sophia Antipolis Cedex - FRANCE Tel.: Fax: Siret N NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N 7803/88 Important notice Individual copies of the present document can be downloaded from: The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on printers of the PDF version kept on a specific network drive within Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other documents is available at If you find errors in the present document, send your comment to: editor@etsi.fr Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. European Telecommunications Standards Institute All rights reserved. DECT TM, PLUGTESTS TM and UMTS TM are Trade Marks of registered for the benefit of its Members. TIPHON TM and the TIPHON logo are Trade Marks currently being registered by for the benefit of its Members. 3GPP TM is a Trade Mark of registered for the benefit of its Members and of the 3GPP Organizational Partners.

3 2 TS V4.1.1 ( ) Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to. The information pertaining to these essential IPRs, if any, is publicly available for members and non-members, and can be found in SR : "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to in respect of standards", which is available from the Secretariat. Latest updates are available on the Web server ( Pursuant to the IPR Policy, no investigation, including IPR searches, has been carried out by. No guarantee can be given as to the existence of other IPRs not referenced in SR (or the updates on the Web server) which are, or may be, or may become, essential to the present document. Foreword This Technical Specification (TS) has been produced by 3rd Generation Partnership Project (3GPP). The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or GSM identities. These should be interpreted as being references to the corresponding deliverables. The cross reference between GSM, UMTS, 3GPP and identities can be found under

4 3 TS V4.1.1 ( ) Contents Intellectual Property Rights...2 Foreword...2 Foreword Scope References Abbreviations Overview of Short Message Service (SMS) support Protocols and protocol architecture Use of channels (A/Gb mode only) Layer 2 SAPI 3 handling for circuit switched in A/Gb mode Layer 2 (LLC) GPRS support (A/Gb mode only) GSMS entity in Iu mode Service definition General Service provided by the CM-sublayer Definition of primitives on the MS side ABORT-REQuest DATA-REQuest DATA-INDication ESTablish-REQuest ESTablish-INDication ERROR-INDication RELease-REQuest Definition of primitives on the network side ABORT-REQuest DATA-REQuest DATA-INDication ESTablish-REQuest ESTablish-INDication ERROR-INDication RELease-REQuest Service provided by SM-RL Definition of primitives on the MS side SM-RL-DATA-REQuest SM-RL-DATA-INDication SM-RL-MEMORY-AVAILABLE-REQuest SM-RL-REPORT-REQest SM-RL-REPORT-INDication Definition of primitives on the network side SM-RL-DATA-REQuest SM-RL-DATA-INDication SM-RL-MEMORY-AVAILABLE-INDication SM-RL-REPORT-REQuest SM-RL-REPORT-INDication [Void] CM-procedures General Short Message Control states SMC-CS states at the MS side of the radio interface Mobile Originating Case MO-Idle (State 0) MO-MM-connection pending (State 1) MO-Wait for CP-ACK (State 2)...19

5 4 TS V4.1.1 ( ) MO-MM-connection established (State 3) Mobile Terminating case MT-Idle (State 0) MT-Wait for CP-ACK (State 2) MT-MM-connection established (State 3) SMC-GP states at the MS side of the radio interface Mobile Originating Case MO-Idle (State 0) MO-GMM-connection pending (State 1) (Iu mode only) MO-Wait for CP-ACK (State 2) MO-Wait for CP-Data (State 3) Mobile Terminating case MT-Idle (State 0) MT-Wait for RP-ACK (State 1) MT-Wait for CP-ACK (State 2) SMC-CS states at the network side of the radio interface Mobile Originating Case MO-Idle (State 0) MO-Wait for CP-ACK (State 2) MO-MM-connection established (State 3) Mobile Terminating Case MT-Idle (State 0) MT-MM-connection pending (State 1) MT-Wait for CP-ACK (State 2) MT-MM-connection established (State 3) SMC-GP states at the network side of the radio interface Mobile Originating Case MO-Idle (State 0) MO-Wait for RP-ACK (State 1) MO-Wait for CP-ACK(State 2) Mobile Terminating Case MT-Idle (State 0) MT-Wait for CP-ACK (State 1) MT-Wait for CP DATA (State 2) Short Message Control procedures MM-connection establishment for circuit switched service RPDU transfer for circuit switched service RPDU transfer for GPRS Release of MM and CM connections Abnormal cases Concatenating short message or notification transfers SM-RL-procedures General Transition states of SMR entity SMR-states at the MS-side of the radio interface Idle (State 0) Wait for RP-ACK (State 1) a Wait to send RP-ACK (State 3) Wait for RETRANS TIMER (State 4) SMR-states at the network side of the radio interface Idle (State 0) Wait for RP-ACK (State 1) Wait to send RP-ACK (State 3) Short Message Relay procedures TPDU relaying [Void] Notification relaying MS side Idle state Wait for RP-ACK state Wait for RETRANS Timer state...29

6 5 TS V4.1.1 ( ) Network side Idle state Wait to Send RP-ACK state Abnormal cases Message functional definitions and content General Messages for short message or notification transfer on CM CP-DATA CP-ACK CP-ERROR Messages for short message and notification transfer on SM-RL RP-DATA RP-DATA (Network to Mobile Station) RP-DATA (Mobile Station to Network) RP-SMMA RP-ACK RP-ERROR Message format and information elements coding CP-messages General Protocol Discriminator and Transaction Identifier Message type Other required information elements CP-User data element CP-Cause element RP-messages General Message type indicator (MTI) Message reference [Void] Other required information elements Originator address element Destination address element RP-User data element RP-Cause element Handling of unknown, unforeseen, and erroneous protocol data General CP Error Handling Message too short Unknown or unforeseen transaction identifier Unknown or unforeseen message type Non-semantical mandatory information element errors Messages with semantically incorrect contents RP Error Handling Message too short Unknown or unforeseen Message Reference Unknown or unforeseen message type Non-semantical mandatory information element errors Messages with semantically incorrect contents Timers...41 Annex A (informative): Arrow diagrams...42 Annex B (normative): SDL-description of the CM-layer...49 B.1 Introduction...49 Annex C (informative): Arrow diagrams...78 Annex D (normative): SDL-description of the short message relay layer...84

7 6 TS V4.1.1 ( ) D.1 Introduction...84 Annex E (informative): Cause definition...92 Annex F (informative): LAPDm SAPI 3 handling for short message service...97 Annex G (informative): Change history History...105

8 7 TS V4.1.1 ( ) Foreword This Technical Specification (TS) has been produced by the 3 rd Generation Partnership Project (3GPP). The present document defines the Short Message Service (SMS) support on mobile radio interface within the 3GPP system. The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows: Version x.y.z where: x the first digit: 1 presented to TSG for information; 2 presented to TSG for approval; 3 or greater indicates TSG approved document under change control. y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc. z the third digit is incremented when editorial only changes have been incorporated in the document.

9 8 TS V4.1.1 ( ) 1 Scope The present document specifies the procedures used across the mobile radio interface by the signalling layer 3 function Short Message Control (SMC) and Short Message Relay function (SM-RL) for both circuit switched in A/Gb mode and GPRS. 1.1 References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. For a specific reference, subsequent revisions do not apply. For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document. [1] [Void] [1a] 3GPP TR : "Vocabulary for 3GPP Specifications". [2] 3GPP TS : "Technical realization of the Short Message Service (SMS) Point-to-Point (PP)". [3a] 3GPP TS : "General Packet Radio Service (GPRS); Service description; Stage 2". [3] 3GPP TS : "Mobile Station - Base Station System (MS - BSS) interface; Data Link (DL) layer specification". [4] 3GPP TS : "Mobile radio interface signalling layer 3; General aspects". [5] 3GPP TS : "Mobile radio interface layer 3 specification". [5a] [5b] [5c] [6a] 3GPP TS : "Radio Resource Control (RRC); Protocol Specification". 3GPP TS : "3G Security; Security Architecture". 3GPP TS : "Subscriber Identity Modules (SIM); Functional characteristics". 3GPP TS : "General Packet Radio Service (GPRS); Logical Link Control (LLC) layer specification ". [6] ISO 7498: "Information processing systems - Open Systems Interconnection - Basic Reference Model". [7] 3GPP TS : "Mobile radio interface layer 3 specification; Radio Resource Control Protocol". 1.2 Abbreviations For the purpose of the present document, the abbreviations given in 3GPP TR and the following apply: RR connection: a RR connection is a dedicated physical circuit switched domain connection used by the two RR or RRC peer entities to support the upper layers' exchange of information flows. PS signalling connection: is a peer to peer UMTS connection between MS and CN packet domain node. GPRS: Packet Services for GSM and UMTS system. The label (A/Gb mode only): indicates this section or paragraph applies only to GSM system. For multi system case this is determined by the current serving radio access network.

10 9 TS V4.1.1 ( ) The label (Iu mode only): indicates this section or paragraph applies only to UMTS system. For multi system case this is determined by the current serving radio access network. In A/Gb mode,...: Indicates this paragraph applies only to GSM System. For multi system case this is determined by the current serving radio access network. In Iu mode,...: Indicates this paragraph applies only to UMTS System. For multi system case this is determined by the current serving radio access network. SIM: Subscriber Identity Module (see 3GPP TS ). This specification makes no distinction between SIM and USIM. MS: Mobile Station. This specification makes no distinction between MS and UE. 2 Overview of Short Message Service (SMS) support The purpose of the Short Message Service is to provide the means to transfer messages between a GSM PLMN Mobile Station (MS) and a Short Message Entity via a Service Centre, as described in 3GPP TS The terms "MO" - Mobile Originating - and "MT" - Mobile Terminating - are used to indicate the direction in which the short message is sent. The present document describes the procedures necessary to support the Short Message Service between the MS and the MSC or SGSN and vice versa, as described in 3GPP TS The procedures are based on services provided by the Mobility Management sublayer as described in 3GPP TS / for CS in A/Gb mode and CS/PS services in Iu mode and the Logical Link Control layer described in 3GPP TS for GPRS services. 2.1 Protocols and protocol architecture In Iu mode only, integrity protected signalling (see 3GPP TS , subclause Integrity Protection of Signalling Messages, and in general, see 3GPP TS ) is mandatory. In Iu mode only, all protocols shall use integrity protected signalling. Integrity protection of all SMS signalling messages is the responsibility of lower layers. It is the network which activates integrity protection. This is done using the security mode control procedure (3GPP TS ). The hierarchical model in figure 2.1a shows the layer structure of the MSC and the MS in A/Gb mode. The hierarchical model in figure 2.1c shows the layer structure of the SGSN and the MS in Iu mode. MSC MS SM-AL SM-TL SM-RL SMR < SM-RP protocol > SMR CM-sublayer SMC < SM-CP protocol > SMC MM-sublayer RR-sublayer Figure 2.1a/3GPP TS : Protocol hierarchy for circuit switched service The hierarchical model in figure 2.1b shows the layer structure of the SGSN and the MS in A/Gb mode.

11 10 TS V4.1.1 ( ) SGSN MS SM-AL SM-TL SM-RL SMR < SM-RP protocol > SMR CM-sublayer SMC < SM-CP protocol > SMC LLC-sublayer GRR-sublayer Figure 2.1b/3GPP TS : Protocol hierarchy for GPRS in A/Gb mode SGSN MS SM-AL SM-TL SM-RL SMR < SM-RP protocol > SMR CM-sublayer SMC < SM-CP protocol > SMC GMM-sublayer Figure 2.1c/3GPP TS : Protocol hierarchy for packet switched service in Iu mode The CM-sublayer, in terms of the Short Message Service Support, provides services to the Short Message Relay Layer. On the MS-side the Short Message Relay Layer provides services to the Short Message Transfer Layer. The Short Message Relay Layer is the upper layer on the network side (MSC or SGSN), and the SM-user information elements are mapped to TCAP/MAP. The peer protocol between two SMC entities is denoted SM-CP, and between two SMR entities, SM-RP. Abbreviations: SM-AL SM-TL SM-RL SM-RP SMR CM-sub SM-CP SMC MM-sub GMM-sub RR-sub LLC-sub GRR-sub Short Message Application Layer Short Message Transfer Layer Short Message Relay Layer Short Message Relay Protocol Short Message Relay (entity) Connection Management sublayer Short Message Control Protocol Short Message Control (entity) Mobility Management sublayer GPRS Mobility Management sublayer Radio Resource Management sublayer Logical Link Control sublayer GPRS Radio Resource sublayer in GSM

12 11 TS V4.1.1 ( ) 2.2 Use of channels (A/Gb mode only) Table 2.1/3GPP TS summarizes the use of channels for the short message service for circuit switched in A/Gb mode. Arrows indicate changes of channel. Table 2.1/3GPP TS : Channels used for short message transfer over circuit switched in A/Gb mode Channel dependency TCH not allocated TCH not allocated -> TCH allocated TCH allocated TCH allocated -> TCH not allocated Channel used SDCCH SDCCH -> SACCH SACCH SACCH -> SACCH opt. SDCCH³ The short message service for GPRS shall be supported by a PDTCH. 2.3 Layer 2 SAPI 3 handling for circuit switched in A/Gb mode General rule: - the Radio Resource Management (RR reference 3GPP TS ) in the Mobile Station and on the network side (i.e. in the BSC) shall establish the acknowledged mode of operation on SAPI 3 whenever needed, i.e. when a message requiring SAPI 3 transfer shall be transmitted; - RR shall control the layer 2 also for SAPI 3, and keep knowledge of the mode; - the network side may initiate release of the acknowledged mode for SAPI 3 either explicitly (by the use of DISC- and UA-frames, see 3GPP TS ) or indirectly by channel release (see 3GPP TS ). This means: - the Mobile Station side will initiate establishment of SAPI 3 acknowledged mode in the case of mobile originating short message transfer; - the network side will initiate establishment of SAPI 3 acknowledged mode in the case of mobile terminating short message transfer; - the network side may choose to keep the channel and the acknowledged mode of operation to facilitate transfer of several short messages for or from the same Mobile Station. The queuing and scheduling function for this should reside in the MSC. 2.4 Layer 2 (LLC) GPRS support (A/Gb mode only) It shall be possible for a GPRS-attached MS of any class (A, B, C) to send and receive short messages over GPRS radio channels. GPRS shall use the unacknowledged mode of LLC frame transfer as described in 3GPP TS , and shall use SAPI 7 to identify the SMS Logical Link Entity within the LLC layer. A description of the different GPRS MS classes can be found in 3GPP TS , and a brief overview is given below: - class A/B MSs may be able to send and receive short messages using either the MM sublayer (using SACCH or SDCCH) or the LLC layer (using PDTCH); - class C MSs may be able to send and receive short messages using only the LLC layer (using the PDTCH). The capability for GPRS-attached class-c MSs to receive and transmit SMS messages is optional. The GSMS entity for GPRS class A/B MS is shown in figure 2.2. The GSMS shall communicate with the MM entity via the GMMSMS-SAP for GPRS Class A/B MO SMS, in order to ascertain which transport service to use. SMS delivery via GPRS is normally a more radio resource efficient method than SMS delivery via CS in A/Gb mode. The delivery path for MO SMS is selected by the MS.

13 12 TS V4.1.1 ( ) SAP SMSMM SMC-GP SMC-CS LLSMS-SAP MMSMS-SAP GMMSMS-SAP Figure 2.2/3GPP TS : GSMS entity for GPRS Class A/B MS 2.5 GSMS entity in Iu mode It shall be possible for a PS-attached MS of any mode of operation to send and receive short messages in Iu mode. A description of the different mode of operation UMTS MS can be found in 3GPP TS , and a brief overview is given below: - CS/PS mode of operation MSs may be able to send and receive short messages using either the MM sublayer or the GMM sublayer; - PS mode of operation MSs may be able to send and receive short messages using only GMM sublayer. The GSMS entity for CS/PS mode of operation MS is shown in figure 2.3. The GSMS shall communicate with the MM entity via the GMMSMS-SAP for CS/PS mode of operation MO SMS in Iu mode, in order to ascertain which transport service to use. The delivery path for MO SMS is selected by the MS. SAP SMSMM SMC-GP SMC-CS PMMSMS-SAP MMSMS-SAP GMMSMS-SAP Figure 2.3/3GPP TS : GSMS entity for CS/PS mode of operation MS in Iu mode

14 13 TS V4.1.1 ( ) 3 Service definition 3.1 General The layer service is described as a set of service primitives. These service primitives are abstractions and attempt to capture only those details of the interaction between the entities that are aspects of the layer service itself. A service primitive neither specifies nor constrains the implementation of entities or the interface between them. The general syntax of a primitive and the initials of them are in line with the 24-series of 3GPP Technical Specifications. NOTE: In order to limit the number of primitives and state definitions to a reasonable amount, a description method has been chosen which does not claim to be totally in line with the formal description method of the layered ISO reference model (ISO 7498) for Open Systems Interconnection. 3.2 Service provided by the CM-sublayer In order to support the Short Message Service, the CM-sublayer provides services to the Short Message Relay Layer. The CM-sublayer services are provided using layer specific functions and lower layer services offered to the CM-sublayer, controlled by short message service control entities called SMCs. An SMC entity in the MS communicates with an SMC entity in the MSC or SGSN by means of a peer protocol, SM-CP (Short Message Service Control Protocol). The arrow diagrams in annex A give an overview of the messaging on the CM-sublayer during a short message transfer. A mobile station supporting the Short Message Service shall have a minimum of two SMC entities per service type (i.e. two for CS GSM and two for GPRS). This enables the MS to receive MT messages during an MO message transfer. To ensure that an MS having the minimum of two SMC entities is able to receive MT messages during an MO message transfer, and to send MO messages during MT message transfer, parallel message transfer in the same direction is prohibited. This means that the SMC entities shall not simultaneously perform messaging in the same direction. The rules for concatenation of message transfers are described in subclause 5.4. The MSC or SGSN shall have a minimum of two SMC entities available each during an MT message transfer to a mobile station, one being reserved for MO message transfer. In an MO message transfer, the MSC or SGSN shall have one SMC entity reserved for handling of an MT message Definition of primitives on the MS side This subclause defines the service primitives used on the MS side. Table 3.1/3GPP TS gives an overview of the service primitives and main parameter linked to the primitives. All necessary control parameters to be used in the Short Message Service are defined in clause 7. All MNSMS service primitives defined in this subclause are passed to an SMC-entity.

15 14 TS V4.1.1 ( ) Table 3.1/3GPP TS : MNSMS service primitives on the MS-side SERVICE PRIMITIVES PARAMETER NAME TYPE ABORT- Req Cause DATA Req MT RPDU Ind MO RPDU EST- Req MO RPDU Ind MT RPDU ERROR- Ind Cause REL- Req Cause ABORT-REQuest A request from an SMR entity to release a CM-connection in abnormal cases. When the CM-sublayer receives this request, and if the MM connection exists, it shall form and send the CP-ERROR message. Irrespective of whether or not the CP-ERROR message was sent, the CM-sublayer shall then release the lower layer services DATA-REQuest A request from an SMR entity to send a RPDU on the established CM-connection. The SMC entity forms the CP-DATA message, the user information element being the RPDU, and transfers the message by means of the lower layer services. NOTE: After reception of an incoming RP-DATA, the SMR entity typically returns the acknowledgement RP-ACK, or an error indication, RP-ERROR, to the Service Centre DATA-INDication An indication used by the SMC entity to pass the user information element (RPDU) of a received CP-DATA message to SM-RL. NOTE: The RPDU is typically an RP-ACK or an RP-ERROR. Normally this service is used to report the outcome of either a MO message transfer attempt or a mobile station memory available notification attempt ESTablish-REQuest A request from an SMR entity to establish a CM-connection. The request contains a RP-DATA UNIT as a parameter. It implies the: - establishment of a CM-connection for this SMR entity; - forming of the CP-DATA message containing the RPDU; and - passing of CP-DATA to the MM-sublayer ESTablish-INDication An indication used by the SMC entity to pass the SM-user information (RPDU) of a received CP-DATA message to SM-RL. It implies completion of the establishment of the CM-connection for this SMR entity.

16 15 TS V4.1.1 ( ) ERROR-INDication An indication used by the SMC entity to pass error information to SM-RL. The error information may be local or relayed by the CP-ERROR message. Use of this service primitive implies release of both CM and MM-connection RELease-REQuest A request to release the CM-connection (if it still exists). Use of this service primitive implies release of the associated CM and MM-connections Definition of primitives on the network side This subclause defines the service primitives used on the network side. Table 3.2/3GPP TS gives an overview of the service primitives and linked main parameter. All MNSMS service primitives defined in this subclause are passed to an SMC-entity. Table 3.2/3GPP TS : MNSMS service primitives on the network side SERVICE PRIMITIVES PARAMETER NAME TYPE ABORT- Req Cause DATA Req MO RPDU Ind MT RPDU EST- Req MT RPDU Ind MO RPDU ERROR- Ind Cause REL- Req Cause ABORT-REQuest A request from an SMR entity to release a CM-connection in abnormal cases. When the CM-sublayer receives this request, it may form and send the CP-ERROR message to release the connection. Irrespective of whether or not the CP-ERROR message was sent, the CM-sublayer shall then release the lower layer services DATA-REQuest A request from an SMR entity to send a RPDU on the established CM-connection. The SMC entity forms the CP-DATA message, the user information element being the RPDU, and transfers the message by means of the lower layer services. NOTE: After reception of an incoming RP-DATA or RP-SMMA the RPDU typically returns the acknowledgement, RP-ACK, or an error indication RP-ERROR, to the Mobile Station DATA-INDication An indication used by the SMC entity to pass the user information element (RPDU) of a received CP-DATA message to SM-RL.

17 16 TS V4.1.1 ( ) NOTE: The RPDU is typically an RP-ACK or an RP-ERROR. Normally this is used to report the outcome of a MT messaging attempt ESTablish-REQuest A request from an SMR entity to transmit a RPDU, containing the SM-user information element; it implies the: - establishment of a CM-connection for this SMR entity; - forming of the CP-DATA message containing the RPDU; and - passing of CP-DATA to the MM-sublayer ESTablish-INDication An indication used by the SMC entity to pass the SM-user information (RPDU) of a received CP-DATA message to SM-RL; it implies completion of the establishment of the CM-connection for this SMR entity ERROR-INDication An indication used by the SMC entity to pass error information to SM-RL. The error information may be local or relayed by the CP-ERROR message. Use of the service primitive implies release of both CM and MM-connection RELease-REQuest A request to release the CM-connection (if it still exists). Use of this service implies release of the associated CM and MM-connections. 3.3 Service provided by SM-RL In order to support the Short Message Service, the Short Message Relay Layer provides services to the Short Message Transfer Layer. The Short Message Relay Layer services are provided using layer specific functions and lower layer services offered to the Short Message Relay Layer, controlled by short message control entities called SMRs. An SMR entity in the MS communicates with an SMR entity in the MSC by means of a peer protocol, SM-RP (Short Message Relay Protocol). The arrow diagrams in annex C give an overview of the messaging on the Short Message Relay Layer used for the Short Message Service. The diagrams in annex C indicate a layer RL. This is not a layer, but the functional interface to the fixed network. The SM-RL is the upper layer in the MSC. Consequently the service primitives passed between SM-RL and RL indicate the interworking function. The requirements on the SM-RL are the same as for the CM-sublayer. This means that there is exactly one SMR entity for each SMC entity, operating as described in subclause Definition of primitives on the MS side This subclause defines the service primitives used on the MS side. Table 3.3/3GPP TS gives an overview of the service primitives and linked main parameters. All SM-RL service primitives defined in this subclause are passed on an SM-RL-connection.

18 17 TS V4.1.1 ( ) Table 3.3/3GPP TS : SM-RL service primitives on the mobile station side SERVICE PRIMITIVES NAME TYPE PARAMETER SM-RL-DATA- Req MO SMS-TPDU SM-RL-MEMORY AVAILABLE Ind MT SMS-TPDU Req See subclause SM-RL-REPORT- Req See subclause Ind See subclause SM-RL-DATA-REQuest A request from the SM-TL entity to pass the SMS-TPDU and necessary control information to SM-RL; it implies: - establishment of an SM-RL connection for MO message transfer; - forming of the RP-DATA message, containing the SMS-TPDU; - transfer of the RP-DATA message as an RPDU in an EST-Req. The purpose of this service is to relay the SMS-TPDU from the mobile station to the peer entity in the MSC SM-RL-DATA-INDication An indication used by the SMR entity to pass the SMS-TPDU and necessary control information of a received RP-DATA message to SM-TL SM-RL-MEMORY-AVAILABLE-REQuest When received without a parameter, this is a request from the SM-TL entity to pass the necessary control information to SM-RL; it implies: - establishment of an SM-RL-connection for transfer of the notification to the network that the mobile has memory available to receive one or more short messages; - forming the RP-SM-MEMORY-AVAILABLE message; and - transfer of the RP-SM-MEMORY-AVAILABLE message as an RPDU in an EST-Req. The SM-TL entity may abort the transmission of an RP-SM-MEMORY-AVAILABLE message by use of a SM-RL-MEMORY-AVAILABLE-REQuest with the added parameter, SMS-MEM-NOTIF-ABORT, being present. This parameter is, of course, defined only on the interface between the SM-TL and SMR entities within the mobile station. Use of this request with the added parameter will have no effect on messages already given to the lower layers for transmission, but will only abort retransmission of the RP-SM-MEMORY-AVAILABLE message by the SMR entity SM-RL-REPORT-REQest A request used by the SM-TL to relay the RP-ACK or RP-ERROR message from the mobile station to the network. This implies transfer of the RP-ACK or RP-ERROR message as an RPDU in an DATA-Req SM-RL-REPORT-INDication An indication used by the SMR entity to pass an acknowledgement (RP-ACK) or error information to SM-TL. The error information may be local or relayed by the RP-ERROR message; it consists of an appropriate cause and optionally extended diagnostic information.

19 18 TS V4.1.1 ( ) Definition of primitives on the network side This subclause defines the service primitives used on the network side. Table 3.4/3GPP TS gives an overview of the service primitives and linked main parameter. All SM-RL service primitives defined in this subclause are passed on an SM-RL-connection. Table 3.4/3GPP TS : SM-RL service primitives on the network side SERVICE PRIMITIVES PARAMETER NAME TYPE SM-RL-DATA- Req MT SMS-TPDU Ind MO SMS-TPDU SM-RL-MEMORY AVAILABLE Ind None SM-RL-REPORT- Req See subclause Ind See subclause SM-RL-DATA-REQuest A request from RL to pass the SMS-TPDU to SM-RL; it implies: - establishment of a SM-RL-connection for MT message transfer; - forming of the RP-DATA message, containing the SMS-TPDU; and - transfer of the RP-DATA message as an RPDU in an EST-Req. The purpose of this service is to relay the SMS-TPDU from the MSC to the peer entity in the mobile station SM-RL-DATA-INDication An indication used by the SMR entity to pass the SMS-TPDU of a received RP-DATA message to RL SM-RL-MEMORY-AVAILABLE-INDication An indication used by the SMR entity to pass to RL the notification to the network that the mobile has memory available to receive one or more short messages SM-RL-REPORT-REQuest A request used by RL (the network interworking function) to relay the RP-ACK or RP-ERROR message from the network to the mobile station. This implies transfer of the RP-ACK or RP-ERROR message as an RPDU in an DATA-Req SM-RL-REPORT-INDication An indication used by the SMR entity to pass an acknowledgement (RP-ACK) or error information to RL. The error information may be local or relayed by the RP-ERROR message.

20 19 TS V4.1.1 ( ) 4 [Void] 5 CM-procedures 5.1 General This clause describes the procedures used by the SMC entity on the Connection Management sublayer. An SMC entity communicates with a corresponding peer entity using an MM-connection for CS in A/Gb and Iu mode or the LLC layer for GPRS in A/Gb mode or the GMM-connection in for PS in Iu mode. Multiple MM-connections may be established at the same time, allowing parallel transactions. The description of the procedures is related to one single transaction. For circuit switched service, the CM-procedures described can only be performed if an MM-connection has been established between the mobile station and the network. For GPRS, no connection has to be established, and thus the CM procedures for GPRS reflect this. Detailed SDL diagrams for SMC entities are contained in annex B. 5.2 Short Message Control states The state transition diagrams for the MO and MT SMC entities on both the MS side and network side are contained in annex B SMC-CS states at the MS side of the radio interface Mobile Originating Case The states described in this clause are for an SMC entity in an MS handling mobile originating short message transfer and notification to the network that the mobile has memory available to receive one or more short messages (referred to below as "notification") MO-Idle (State 0) This state exists when the MO-SMC entity is in idle mode, or when an MO short message transfer or notification ends in a normal or abnormal way MO-MM-connection pending (State 1) This state exists when the MO-SMC has requested the establishment of an MM-connection MO-Wait for CP-ACK (State 2) This state exists after the MO-SMC has initiated the transfer of a CP-DATA message MO-MM-connection established (State 3) This state exists when the MO-SMC has: - received the acknowledgement, CP-ACK; or - received the message CP-DATA (including sending of the associated CP-ACK).

21 20 TS V4.1.1 ( ) Mobile Terminating case The states described in this subclause are for an SMC entity in an MS handling mobile terminating short message transfer MT-Idle (State 0) This state exists when the MT-SMC entity is in idle mode, or when a short message transfer ends in a normal or abnormal way MT-Wait for CP-ACK (State 2) This state exists after the MT-SMC has initiated the transfer of a CP-DATA message MT-MM-connection established (State 3) This state exists when the MT-SMC has: - received the acknowledgement, CP-ACK; or - received the message CP-DATA (including sending of the associated CP-ACK) SMC-GP states at the MS side of the radio interface Mobile Originating Case The states described in this clause are for an SMC-GP entity in a GPRS MS handling mobile originating short message transfer and notification to the network that the mobile has memory available to receive one or more short messages (referred to below as "notification") MO-Idle (State 0) This state exists when the MO-SMC entity is in idle mode, or when an MO short message transfer or notification ends in a normal or abnormal way MO-GMM-connection pending (State 1) (Iu mode only) This state exists when the MO-SMC has requested the establishment of an PS signalling connection MO-Wait for CP-ACK (State 2) This state exists after the MO-SMC has initiated the transfer of a CP-DATA message MO-Wait for CP-Data (State 3) This state exists when the MO-SMC has received the acknowledgement, CP-ACK Mobile Terminating case The states described in this subclause are for an SMC-GP entity in an GPRS MS handling mobile terminating short message transfer MT-Idle (State 0) This state exists when the MT-SMC entity is in idle mode, or when a short message transfer ends in a normal or abnormal way.

22 21 TS V4.1.1 ( ) MT-Wait for RP-ACK (State 1) This state exists after the MT-SMC has received the message CP-DATA (including sending of the associated CP-ACK) MT-Wait for CP-ACK (State 2) This state exists when the MT-SMC has initiated the transfer of the CP DATA message SMC-CS states at the network side of the radio interface Mobile Originating Case The states described in this subclause are for an SMC entity in an MSC handling both mobile originating short message transfer and notification to the network that the mobile has memory available to receive one or more short messages (referred to below as "notification") MO-Idle (State 0) This state exists when the MO-SMC entity is in idle mode, or when a short message transfer or notification ends in a normal or abnormal way MO-Wait for CP-ACK (State 2) This state exists after the MO-SMC has initiated the transfer of a CP-DATA message MO-MM-connection established (State 3) This state exists when the SMC has: - received the acknowledgement, CP-ACK; or - received the message CP-DATA (including sending of the associated CP-ACK) Mobile Terminating Case The states described in this subclause are for an SMC entity in an MSC handling mobile terminating short message transfer MT-Idle (State 0) This state exists when the MT-SMC entity is in idle mode, or when a short message transfer ends in a normal or abnormal way MT-MM-connection pending (State 1) This state exists when the MT-SMC has requested an MM-connection for mobile terminating short message transfer MT-Wait for CP-ACK (State 2) This state exists after the SMC has initiated the transfer of a CP-DATA message MT-MM-connection established (State 3) This state exists when the SMC has: - received the acknowledgement, CP-ACK; or - received the message CP-DATA (including sending of the associated CP-ACK).

23 22 TS V4.1.1 ( ) SMC-GP states at the network side of the radio interface Mobile Originating Case The states described in this subclause are for an SMC-GP entity in an SGSN handling both mobile originating short message transfer and notification to the network that the mobile has memory available to receive one or more short messages (referred to below as "notification") MO-Idle (State 0) This state exists when the MO-SMC entity is in idle mode, or when a short message transfer or notification ends in a normal or abnormal way MO-Wait for RP-ACK (State 1) This state exists after the MO-SMC has received the message CP-DATA (including sending of the associated CP-ACK) MO-Wait for CP-ACK(State 2) This state exists when the SMC has received the RP acknowledgement, RP-ACK Mobile Terminating Case The states described in this subclause are for an SMC-GP entity in an SGSN handling mobile terminating short message transfer MT-Idle (State 0) This state exists when the MT-SMC entity is in idle mode, or when a short message transfer ends in a normal or abnormal way MT-Wait for CP-ACK (State 1) This state exists after the SMC has initiated the transfer of a CP-DATA message MT-Wait for CP DATA (State 2) This state exists when the SMC has received the acknowledgement, CP-ACK. 5.3 Short Message Control procedures The procedures needed for short message control are: - connection establishment procedures; - RP Data Unit (RPDU) transfer procedures; - connection release procedures; and - procedures for abnormal cases. The procedures of subclause 5.3 are described with respect to one particular instance of an SMC entity. Different SMC entities are identified by their Transaction Identifier. Messages with Transaction Identifiers that do not correspond to this particular instance of the SMC entity are not treated by it.

24 23 TS V4.1.1 ( ) MM-connection establishment for circuit switched service When an SMC entity is in the Idle state and transfer of an RPDU is requested, the peer to peer connection between the MM-sublayers in the MS and the network (MSC) has to be established. The SMC entity on the originating side requests the MM-sublayer to establish an MM-connection, and enters the MM-Connection Pending state. After completion of the MM-connection establishment, a confirmation is given to the originating side to indicate that the MM sublayer is ready for RPDU transfer. The MM-connection establishment is indicated to the SMC entity at the destination side when the CP-DATA message has been received by the MM-sublayer (in line with 3GPP TS ). The destination side SMC entity then sends a CP-ACK and enters the MM-Connection Established state RPDU transfer for circuit switched service In A/Gb mode, when an SMC entity in the MM-Connection Pending state is informed that an MM-connection has been established, the SMC entity forwards the CP-DATA message containing the RPDU, sets the timer TC1* and enters the Wait for CP-ACK state. In Iu mode, when an SMC-GP entity in the MS side is in the Idle state and transfer of an RPDU is requested, the SMC- GP entity on the originating side requests the MM-sublayer to establish an PS signalling connection, and enters the GMM-Connection Pending state. In Iu mode, in the MS, after completion of the PS signalling connection establishment, a confirmation is given to the originating side to indicate that the MM sublayer is ready for RPDU transfer. In Iu mode, in the MS, after confirmation of the PS signalling connection establishment, the SMC-GP entity on the originating side forwards the CP-DATA message to the GMM sublayer. This contains the RPDU, and also the SMC-GP entity sets the timer TC1* and enters the Wait for CP-ACK state. In Iu mode, when an SMC-GP entity in the network side is in Idle state and transfer of an RPDU is requested, the SMC- GP entity on the originating side forwards the CP-DATA message to the GMM sublayer. This contains the RPDU, and also the SMC-GP entity sets the timer TC1* and enters the Wait for CP-ACK state. The value of TC1* may vary with the length of the CP-DATA message and the channel type that is being used for its transmission. However, the value of TC1* shall be sufficiently great to allow the lower layers to transmit the CP-DATA and CP-ACK messages and to allow for some retransmissions of layer 2 frames. If an SMC entity in the Wait for CP-ACK state gets an indication that the CP-DATA message has probably been lost (e.g. due to dedicated channel assignment, hand over, assignment failure, hand over failure, or a SAPI 3 data link failure) then, as an implementation option, that SMC entity may reduce the time until expiry of TC1*. If the timer TC1* expires in the Wait for CP-ACK state, the CP-DATA message is retransmitted and the state Wait for CP-ACK is re-entered. The maximum number of CP-DATA message retransmissions is an implementation option but shall be either 1, 2 or 3. If the timer TC1* expires after the maximum number of retransmission attempts, an error indication is passed to SM-RL and an MM-connection release request is passed to the MM-sublayer. The Idle state is then entered. On receipt of the CP-ACK message in the Wait for CP-ACK state, the SMC resets the timer TC1* and enters the MM-Connection Established state. In A/Gb mode, when receiving a CP-DATA message in the MM-Connection Established state, the SMC entity checks the parameters relevant to the CP protocol. If these are valid, the RPDU is passed to the SM-RL, the CP-ACK message is sent and the state MM-Connection Established is re-entered. In Iu mode, when receiving a CP-DATA message from the GMM sublayer, the SMC-GP entity checks the parameters relevant to the CP protocol. If these are valid, the RPDU is passed to the SM-RL, the CP-ACK message is sent. If an SMC entity in the Idle state is unable to accept a CP-DATA message, it sends a CP-ERROR message followed by an MM-connection release request and then enters the Idle state.

25 24 TS V4.1.1 ( ) When receiving a DATA-Req primitive in the MM-Connection Established state, the SMC entity forwards a CP-DATA message containing the RPDU to the MM-sublayer, sets the timer TC1* and enters the Wait for CP-ACK state RPDU transfer for GPRS When an SMC-GP entity is in the Idle state and transfer of an RPDU is requested, the SMC-GP entity on the originating side forwards the CP-DATA message to the LLC sublayer. This contains the RPDU, and also the SMC-GP entity sets the timer TC1* and enters the Wait for CP-ACK state. The value of TC1* may vary with the length of the CP-DATA. However, the value of TC1* shall be sufficiently great to allow the lower layers to transmit the CP-DATA and CP-ACK messages and to allow for some re-transmissions of layer 2 frames. If an SMC entity in the Wait for CP-ACK state gets an indication that the CP-DATA message has probably been lost then, as an implementation option, that SMC-GP entity may reduce the time until expiry of TC1*. If the timer TC1* expires in the Wait for CP-ACK state, the CP-DATA message is retransmitted and the state Wait for CP-ACK is re-entered. The maximum number of CP-DATA message re-transmissions is an implementation option but shall be either 1, 2 or 3. If the timer TC1* expires after the maximum number of retransmission attempts, an error indication is passed to SM-RL. The Idle state is then entered. On receipt of the CP-ACK message in response to the CP-DATA (RP DATA) message in the Wait for CP-ACK state, the SMC-GP resets the timer TC1* and enters the Wait for CP DATA state. On receipt of the CP-ACK message in response to the CP-DATA (RP ACK) message in the Wait for CP-ACK state, the SMC-GP resets the timer TC1* and enters the Idle State. When receiving a CP-DATA message form the LLC sublayer, the SMC-GP entity checks the parameters relevant to the CP protocol. If these are valid, the RPDU is passed to the SM-RL, the CP-ACK message is sent. If an SMC entity in the Idle state is unable to accept a CP-DATA message, it sends a CP-ERROR message and then enters the Idle state Release of MM and CM connections With the exception of error situations, release of the MM and CM connection is controlled by the SM-RL. When an SMC entity in the Wait for CP-ACK state receives a release request from SM-RL, this request is stored until the next state (either MM Connection Established or Idle) is entered. If the Idle state is entered, the request is discarded. If the MM Connection Established state is entered, or if the SMC entity receives a release request from SM-RL in this state, an MM-connection release request is sent to the MM-sublayer and the SMC entity enters the Idle state Abnormal cases Abnormal cases that shall be handled by the SMC entity in any state can be classified into five cases: - Upper Layer Abort: errors occurring in the SM-RL may cause the SM-RL to send an ABORT Request to the SMC entity; - CP-Layer Abort: errors occurring within the SMC entity itself may require termination of all activities related to that transaction identifier; - Lower Layer Abort: errors occurring within the layers beneath the CP-layer may cause an MMSM-ERROR Indication or a GMMSMS-ERROR Indication to be sent to the SMC entity; - CP-Layer Protocol Errors: errors occurring within the protocol exchange between the SMC entities may result in the sending of a CP-ERROR message between the entities; - Lower Layer Release: events occurring within the layers beneath the CP layer may cause an MMSM-REL Indication to be sent to the SMC entity.